Vegetation succession process induced by reforestation in erosion area

Reforestation is one of the most important and efficient measures of water and soil conservation. Based on field investigation at the Shangyang Soil Conservation and Reforestation Station in Huizhou, Guangdong Province, China, vegetation development, the vegetation succession process, and soil erosion variation are studied in this paper. The regional vegetation consists mainly of monsoon evergreen broad-leaved forest. The area was deforested and became a bare hilly area with extremely high soil erosion in the 1960s and 1970s. Then the area was closed for vegetation recovery. Under natural conditions the vegetation development and the succession process are slow. Soil erosion, strong sunshine, and evaporation slow vegetation development. About 25 years later, the vegetation cover merely reached 35% or so. The dominating vegetation types were heliophilous herbages and shrubs, which formed a poorly developed shrub-herbage community. The erosion is still high. On the other hand, reforestation with selected species of trees dramatically sped up the vegetation succession process. About 12 years after reforestation, the vegetation cover of the artifical Acacia auriculaeformis forest at the Shangyang Station reached 90% and erosion was on controlled. After 23 years, understory vegetation consisting of local species has developed in the artificial forest. The planted trees and naturally developing plants, shrubs, bamboo, trees, and liana formed a complicated vegetation community with three layers. It takes about 60 years for the vegetation to progress from bare land to second growth forest under natural conditions. Reforestation may speed up the vegetation succession process. The time may be reduced to 20 years. Reforestation is an effective measure of vegetation restoration and erosion control in this area.